The search for a safe, orally ingested opiate analgesic is one of the oldest challenges known in medicinal chemistry. Opiates are incredibly well known for the treatment of acute or chronic severe pain, and are arguably one of the oldest drugs known to man. The market for chronic pain treatment is a substantial one, including the treatment of chronic pain associated with fibromyalgia, arthritis, sports injuries and malignancies. Current pain management protocols have resulted in a multi-billion dollar prescription market, with a pain management drug, hydrocodone/APAP, ranked number one in prescription drug sales in 2010.
Unfortunately, pain management drugs, particularly opiates, give rise to euphoria and other side effects when taken by healthy individuals, and thus opiates are extremely addictive. The diversion of prescription drugs for substance abuse is a societal issue that cannot be ignored.
SUBOXONE® is particularly well known prescription drug for treating narcotic addiction. Individuals addicted to narcotics may suffer from a serious physical dependence, resulting in potentially dangerous withdrawal. One well known method by which to treat narcotic addiction is to provide a reduced amount of opiate, in an amount sufficient to satisfy the addict's urge for the narcotic, but not in an amount sufficient to induce euphoria, commonly referred to as a “high.” SUBOXONE® includes a particularly potent opiate, buprenorphine, along with an antagonist, naloxone, providing both a reduced euphoric effect and potentially avoiding opiate extraction (and subsequent abuse) by addicts. The narcotic antagonist binds to a receptor in the brain to block the receptor, thus reducing the effect of the opiate. SUBOXONE® was initially developed as an orally ingestible tablet. However, medicaments containing buprenorphine in tablet form have the potential for abuse, regardless of the presence of naloxone as an antagonist, primarily due to the slow speed at which the tablet dissolved. SUBOXONE® films were subsequently developed having a far faster dissolution speed that provides direct buccal absorption of the buprenorphine in a form that could not be easily removed from the mouth once administered, thereby retarding abuse. SUBOXONE® films are described in United States Patent Application Publication No. 2011/0033541, hereby incorporated by reference herein. Unfortunately, the buccal absorption of opiate translates into a shorter period of efficacy for the patient.
Thus there remains a need in the art for longer acting opiate drug forms for the treatment of addiction. There further exists a need in the art for opiates in film-form providing a more extended period of efficacy for the treatment of chronic or acute pain.